Datasheet
ADS7844
12-Bit, 8-Channel Serial Output Sampling
ANALOG-TO-DIGITAL CONVERTER
FEATURES
● SINGLE SUPPLY: 2.7V to 5V
● 8-CHANNEL SINGLE-ENDED OR
4-CHANNEL DIFFERENTIAL INPUT
● UP TO 200kHz CONVERSION RATE
● ±1 LSB MAX INL AND DNL
● NO MISSING CODES
● 72dB SINAD
● SERIAL INTERFACE
● 20-LEAD QSOP AND
20-LEAD SSOP PACKAGES
● ALTERNATE SOURCE FOR MAX147
DESCRIPTION
The ADS7844 is an 8-channel, 12-bit sampling analog-to-
digital converter (ADC) with a synchronous serial interface.
Typical power dissipation is 3mW at a 200kHz throughput
rate and a +5V supply. The reference voltage (V
REF
) can be
varied between 100mV and V
CC
, providing a corresponding
input voltage range of 0V to V
REF
. The device includes a
shutdown mode that reduces power dissipation to under
1µW. The ADS7844 is ensured down to 2.7V operation.
Low power, high speed, and onboard multiplexer make the
ADS7844 ideal for battery-operated systems such as personal
digital assistants, portable multichannel data loggers, and
measurement equipment. The serial interface also provides
low-cost isolation for remote data acquisition. The ADS7844
is available in a 20-lead QSOP package and the MAX147
equivalent 20-lead SSOP package and is ensured over the
–40°C to +85°C temperature range.
APPLICATIONS
● DATA ACQUISITION
● TEST AND MEASUREMENT
● INDUSTRIAL PROCESS CONTROL
● PERSONAL DIGITAL ASSISTANTS
● BATTERY-POWERED SYSTEMS
CDAC
SAR
Comparator
Eight
Channel
Multiplexer
Serial
Interface
and
Control
CH4
CH5
CH6
CH7
COM
V
REF
CH0
CH1
CH2
CH3
CS
SHDN
DIN
DOUT
BUSY
DCLK
A
D
S
7
8
4
4
ADS7844
SBAS100A – JANUARY 1998 – REVISED OCTOBER 2003
www.ti.com
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright © 1998-2003, Texas Instruments Incorporated
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
All trademarks are the property of their respective owners.